Ranunculus arvensis

This annual plant flowers from May to July (5). It is visited by small flies (2).

Corn buttercup produces yellow flowers with shiny petals on an erect, leafy stem (2). The leaves are split into narrow lobes (5), and the seed heads (called achenes) are extremely spiky (3), and have earned this buttercup the alternative local names of Devil's claws, Devil-on-all-sides, and hellweed (4).

Mediterranean region.

Europe, Mediterranean region, West Asia to India.

Ranunculus arvensis var. tuberculatus DC.:
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Ranunculus arvensis L.:
Canada (North America)
United States (North America)
China (Asia)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

introduced; Ark., Calif., D.C., Ga., Idaho, Ill., Kans., La., Miss., Mo., N.J., N.Y., N.C., Oreg., Pa., S.C., Tenn., Utah, Wash.; South America; native to Eurasia; Pacific Islands; Australia.

United States

Origin: Exotic

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Formerly widespread, but now very scarce (3) and only seen regularly in the south of England (5). It also occurs at a few sites in Wales, south-west England and some scattered localities in the north-west of England and Scotland (2). Elsewhere it is found in central and southern Europe, North Africa and west Asia, reaching as far east as India (2).

Herbs annual. Stems ca. 30 cm, sparsely appressed puberulent, branched. Basal leaves 3--5; petiole 1.6--6 cm, sparsely puberulent; blade 3-lobed, 3-partite, or 3-sect, obovate or broadly rhombic, 1.5--3.5 × 1.5--4 cm, papery, sparsely appressed puberulent, base cuneate or broadly cuneate, lobes narrowly cuneate, 2- or 3-dentate at apex. Stem leaves petiolate or sessile, 1- or 2-ternate, ultimate lobes narrowly cuneate or linear-lanceolate. Flowers leaf-opposed, ca. 1 cm in diam. Pedicel 2--4 cm, appressed puberulent. Receptacle puberulent. Sepals 5, narrowly ovate, ca. 5 mm, abaxially appressed puberulent. Petals 5, obovate, ca. 5 × 3.8 mm, nectary pit covered by a scale, apex rounded. Stamens numerous. Aggregate fruit subglobose, ca. 1.2 cm in diam. Achene complanate, elliptic, ca. 5 × 3.5 mm, glabrous, spiny, spines up to 2 mm; style persistent, ca. 2.6 mm. Fl. Apr--May.

Stems erect or ascending, sparsely pilose. Basal and lower cauline leaf blades obovate to rhombic in outline, 3-parted or 3(-5)-foliolate, 1.8-5.2 × 1.6-4.2 cm, leaflets oblanceolate or divided into oblanceolate or linear segments, leaflet base narrowly acuminate, margins entire or distally dentate, apex rounded or acuminate. Flowers pedicellate; receptacle sparsely hispid; sepals 5, spreading, 4-7 × 1-2 mm, strigose; petals 5, 5-8 × 2-4 mm. Heads of achenes discoid, 8-9 mm across; achenes 5-8 per head, 4-6.4 × 2.8-4.4 mm, faces and margin covered with long spines, glabrous; beak lance-subulate, straight, 1.6-3.8 mm.

Ranunculus arvensis var. tuberculatus de Candolle

Grasslands, ephemeral pools, disturbed areas; 0-1200m.

This species is a weed of cornfields (3), and seems to prefer calcareous soils (2) and clay (6). It also occasionally occurs on disturbed ground, such as on road-sides (2).

Naturalized in sandy places along roads. Anhui, Hubei [native to W Asia and Europe].

Flowering spring (Mar-Jun).

The following is a representative barcode sequence, the centroid of all available sequences for this species.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 3
Specimens with Barcodes: 5
Species With Barcodes: 1

Rounded Global Status Rank: GNR - Not Yet Ranked

United States

Rounded National Status Rank: NNA - Not Applicable

No conservation designations.

It is likely that agricultural intensification is responsible for the decline of this once common species (4), starting at the end of the nineteenth century when seed cleaning techniques were improved (2). Like all weeds of arable land, corn buttercup faces the more modern threats of herbicide and fertiliser use, the loss of field-margins, the use of more productive and competitive crops and alterations in the traditional style of crop rotation (4).

Very little direct conservation action has been targeted at this species. It may benefit from agri-environment schemes.